Low-power hand-held transaction device

ABSTRACT

An electronic hand-held device and method for inputting and sending requests and for receiving and outputting responses to the requests. The electronic hand-held device is a coupled to a telecommunications link over which requests are sent and responses are received. The electronic hand-held device can input request data in any number of different information media, including audio tones and voice signals, mechanical input to a keypad, printed bar codes, magnetic data stored in credit cards, and electronic data stored in electronic smart cards. The electronic hand-held device can output responses through an audio speaker, a visual LCD display device, and, optionally, through other output devices including printers. The electronic hand-held device is especially well suited for order entry and acquisition of product information.

RELATED APPLICATIONS

This application is a continuation-in-part application of U.S.application Ser. No. 09/064,395, filed Apr. 22, 1998, now U.S. Pat. No.6,230,970 allowed, which is a continuation-in-part application of U.S.application Ser. No. 8/657,892 filed Jun. 7, 1996, issued Nov. 7, 2000,U.S. Pat. No. 6,144,848, which is a continuation-in-part of U.S.applications Ser. Nos. 08/482,261 now abandoned, 08/485,083 and08/480,614 now U.S. Pat. No. 5,656,824, all filed Jun. 7, 1995.

TECHNICAL FIELD

This invention relates to hand-held telecommunications devices and, inparticular, to an electronic hand-held device for inputting and sendingrequests and for receiving and outputting responses to the requests.

BACKGROUND OF THE INVENTION

The acquisition of goods and services by placing orders with retailersand distributors is a vital component of modern commerce. Severaldifferent technologies for placing and receiving commercial orderscurrently account for the bulk of commercial order entry. Probably themost familiar and natural method of order entry is that of personaltravel to a retail supplier for a face-to-face transaction paid foreither in cash, by check, by credit card, or by an electronic transferof funds. While such face-to-face transactions allow a purchaser tothoroughly inspect the goods and services that are being purchased, andwhile such transactions are relatively secure for both the purchaser andthe retailer, especially when paid for in cash, face-to-facetransactions are extremely inefficient in time and in communicationscosts. A purchaser generally travels to the retailer's place of businessby car or by public transportation at a relatively high cost in time andenergy, often incurring significant risks in personal safety. While acash transaction is relatively secure, the process of bringing the cashto the retailer's place of business and of transporting purchased goodsback to their place of use or storage often may not be secure. Papermoney can be forged, checks can be misappropriated and fraudulentlypassed, credit cards can be misappropriated and fraudulently used, andelectronic funds transfer may be vulnerable to errors and to electronictheft.

A second familiar method for placing an order and receiving goods andservices is by use of the telephone. Many of the above-described risksfor face-to-face transactions are avoided by using the telephone as amedium for commerce. A telephone transaction may be much more efficientin time and in communications costs than traveling to a retailer's placeof business. The risks inherent in traveling and carrying cash areavoided. However, telephone communications are notoriously insecure and,whereas telephone transactions may require less staffing and facilitiesoverhead from the standpoint of a retailer, such transactions stillrequire either human operators or relatively time-inefficient,cumbersome, and often annoying voice menu systems and recorded-voiceorder-entry systems.

Although popular use of the Internet is a relatively recent phenomenon,and use of the Internet as a medium of commerce is an even more recentphenomenon, the Internet has emerged to become one of the fastestgrowing and most technologically sophisticated mediums for order entry.An Internet user can quickly conduct a comparative analysis of products,identify retailers and distributors for those products, place ordersthrough relatively easy mouse and keyboard input, and pay for thetransactions using relatively secure encrypted communications for theexchange of credit card information and other types of electronic fundstransfer. The Internet provides a much richer communications medium thanthe telephone by providing the display of graphical information as wellas text-based and sound-based information. A disadvantage of theInternet is that a user is generally required to use a personalcomputer. Personal computers are expensive, costly to maintain overtime, and inconvenient to carry.

The trends in order entry and commercial transactions are clear. Despitethe disadvantages discussed above, electronic commerce will soon becomethe preferred medium for the exchange of goods and services. In manycases, the increase in time efficiencies and decreases in energy costsand in overheads for staffing and maintaining retail facilities morethan offset the disadvantages in the lack of security and in the expenseof the electronic order input devices, including personal computers,that are currently necessary for electronic commerce. However, in orderto make electronic commerce and electronic order entry fully accessibleto the general public, and even more advantageous with regard to timeand expense, a new, relatively inexpensive, lightweight, and mobilehand-held telecommunications device for order input via a securecommunications path would be desirable. An electronic order-entry devicethat offered the ease of use and the mobility of a wireless telephonewould be especially desirable, and a telecommunications device thatcomprises a multi-media order-entry device and a telephone in onehandheld package would be most desirable. In addition to use in placingorders for products and services, such a hand-held telecommunicationsdevice would find wide application in specifying, acquiring, anddisplaying information. Applications may include scanning barcodescontained in printed materials such as newspapers, magazines, andcatalogs, or contained on products, such as airplane tickets andentertainment event tickets, and providing additional information aboutthe products, including information about an airplane flight orentertainment event identified by the barcode. The additionalinformation provided by such a hand-held telecommunications device couldbe effectively presented as spoken dialogue, displayed text, music, ordisplayed graphics. A one or two-dimensional barcode in a printedmaterial may also contain an access code, such as an IP address, a URL,a web site address, a product/service ID code, a phone number, or otherinformation that rapidly provides a user with secure electronic accessto a host server.

SUMMARY OF THE INVENTION

One embodiment of the present invention provides a small, low-power,hand-held transaction device for inputting requests, transmitting therequests through a telecommunications link to a server computer,receiving responses to the transmitted requests from the servercomputer, and outputting the responses. The low-power, hand-heldtransaction device may receive mechanical input through a keypad, audioinput through a microphone, and at least one other type of input,including printed barcodes and information stored either magnetically orelectronically on credit cards and smart cards. This input is thenencoded and sent to the server via a telecommunication link. Theinformation contained in the responses that are returned from the servercomputer may be output in one or more information output types,including displayed alphanumeric symbols, displayed alphanumeric symbolsand graphically images, voice, music, and printed text and graphicalimages. Orders from the order entry device to the server computer may becombinations of voice commands, bars codes, card information, orkeystrokes. The order entry device may store inputs entered while offline. The stored inputs, such as UPC codes, may be sent to the servercomputer at a later time. The server computer may also providecommunication with a live operator.

For convenience of use, the low-power, hand-held transaction devicedraws the necessary electrical power to operate from internal batteries,a telephone line loop current, or a computer port. Telecommunicationsserver providers however, generally provide relatively small amounts ofelectrical power to wireless phones and accessories in order to extendbattery life. In order to support the variety of input and output mediumhandled by the low-power, hand-held transaction device, careful powermanagement strategies and a number of low-power internal components areincorporated into the low-power, hand-held transaction device.

Various embodiments of the low-power, hand-held transaction device maybe connected to different types of telecommunications links. These typesof telecommunications links include a standard telephone line, a serialport connection to a computer, a wireless telephone, and a PBX telephoneline. The low-power, hand-held transaction device can be used both as atelephone as well as a request-transmitting and response-receivingdevice. The hand-held transaction device may provide peer-to-peerwireless telephone communication, thus providing a mobile wirelesstelephone as well as a transaction capability within a single device.

The low-power, hand-held transaction device includes support for securetransactions at the hardware level. The low-power, hand-held transactiondevice may include a protected memory that is very difficult to accessby devices or monitors external to the low-power, hand-held transactiondevice. Confidential information, such as credit card numbers,addresses, account numbers, and encryption parameters, can be input intothe low-power, hand-held transaction device and stored within theprotected memory. When a credit card number must be included within arequest that is transmitted to the telecommunications link, the creditcard number may be encrypted within the low-power, hand-held transactiondevice prior to transmission. Thus, an unencrypted credit card number isnot accessible to an external device or to a network monitor. Thecredit/debit card information may be keyed in by the user or may beelectronically read in by the hand-held transaction device.

Connecting to an on-line server generally requires use of an accesscode. An access code may be stored in memory of the LHTD or may beentered by a user using a keypad, barcode reader, card reader, or anycombination of these entry methods. A common access code is a phonenumber of an on-line server or Internet access provider. This phonenumber may be entered by a user via a keypad, activated from LHTDmemory, or may be read in via a barcode reader or card reader.

There are an almost limitless number of different applications for theLHTD. For example, a user may see an interesting printed ad with a barcode. The user then may use the LHTD to read a bar code in the ad, afterwhich the LHTD rapidly provides access to a host server that, in turn,provides an instant audio-visual response to the printed ad. In oneapplication, a user employs the LHTD to listen to music clips beforeordering tickets to a musical. In other applications, a user employs theLHTD to read a bar code to get sports scores or flight information. Instill another example, a user uses the LHTD to scan bar codes on drugsto get the latest warnings and instructions in one of several optionallanguages.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a high-level block diagram of the LHTD.

FIG. 2 is a schematic diagram of a dual-power mode amplifier.

FIG. 3 is a block diagram of a LHTD coupled to a standard telephoneline.

FIG. 4 is a more detailed block diagram of the ring sensor, relay, andpower supply components of the LHTD shown in FIG. 3.

FIG. 5 is a block diagram of the LHTD coupled to a computer through anRS232 connection.

FIG. 6 is a block diagram of the power supply used when the LHTD iscoupled to an RS232 connection.

FIG. 7 is a block diagram of one embodiment of a low-power-consumingbarcode reader.

FIG. 8 is a block diagram of the LHTD connected to a cellular/PCStelephone.

FIG. 9 is a flow control diagram for the main firmware routine.

FIG. 10 is a flow control diagram for the firmware routine“process_input.”

FIG. 11 is a flow control diagram for the firmware routine“telephone_input.”

FIG. 12 is a flow control diagram of the firmware routine“online_request.”

FIG. 13 is a flow control diagram for the firmware routine“offline_request.”

FIG. 14 illustrates the external appearance of one embodiment of theLHTD.

FIG. 15 is a detailed block diagram of an embodiment of a LHTD designedfor connection to a telephone line.

FIG. 16 is a circuit diagram for the telephone interface and powersupply for the LHTD shown in FIG. 15.

FIG. 17 is a circuit diagram for the LHTD described by the block diagramof FIG. 15.

FIG. 18 is a circuit diagram for a LHTD designed to be connected to acellular of PCS telephone.

FIG. 19 is a circuit diagram for a LHTD designed to be connected to awireless telephone.

FIG. 20 is a block diagram for a two-unit LHTD designed for connectionto a cordless telephone.

FIG. 21 is a block diagram for a wireless two-unit LHTD designed forconnection to a personal computer.

FIG. 22 is a block diagram for a barcode reader with a separateproximity detector.

FIG. 23 is a block diagram for a LHTD communicating with and powered bya serial port.

FIG. 24 is a circuit diagram for a signal conditioner included in abarcode reader.

FIG. 25 is a block diagram for a smart card interface that may beincluded in a LHTD.

FIG. 26 is a circuit diagram for a magnetic card reader that may beincluded in a LHTD.

FIG. 27 is a circuit diagram for an alternate embodiment of a powersupply for a LHTD designed for connection to a telephone line.

FIG. 28 is a circuit diagram for a serial port power supply.

FIG. 29 is a block diagram for a LHTD specially designed for digitalvoice communications.

FIG. 30 is a circuit diagram for a modem interface to a voice and datamixer included in a LHTD designed for connection to a telephone line.

FIG. 31 is a block diagram of a lightweight, low power transactiondevice integrated with wireless telephone, such as a cellular or PCStelephone.

FIG. 32 is a schematic diagram of the hand-held transaction deviceintegrated with a wireless telephone, such as a cellular or PCStelephone.

DETAILED DESCRIPTION OF THE INVENTION

Various embodiments of the present invention provide low-power,hand-held transaction devices (“LHTDs”) that can be connected to varioustypes of telecommunications links. These different types oftelecommunication links may include a standard telephone line, a PBXtelephone line, a wireless telephone, a personal communication system(“PCS”) telephone, a cordless telephone, and an RS232 or universalserial bus (“USB”) to a computer that is in turn coupled to a remoteserver computer via a telecommunications link. A LHTD may be a plug-inmodule to a telephone or an LHTD and a wired or wireless transceiver maybe designed into single, hand-held package performing the functions ofboth a multimedia order entry device and a telephone. The LHTD orderentry device and the telecommunication link may share electrical andmechanical components, as well as a power source, such as telephone loopcurrent, wireless phone battery, or a computer port.

Various embodiments of present invention use different types of powersources. In the interest of brevity, the phrase “drawing power from thetelecommunications link,” and other such descriptive phrases, isintended to refer to the drawing of power from any of the differenttypes of power sources. For example, telephone systems provide powerthrough telephone lines. Serial RS232 or USB computer ports providepower from handshake lines or from a power pin. Cellular/PCS phonesprovide power through external connectors. Embodiments of the presentinvention that are built-in embodiments within wireless phones drawpower from wireless phone batteries.

Various embodiments of the LHTD include different types of data inputcomponents for inputting data from different types of data-containingmedia. LHTDs generally contain a microphone for inputting audio data,including voice data, and a keypad for inputting alphanumeric symbols.In addition, a LHTD may contain a barcode reader for reading andinputting printed barcodes, a magnetic card reader for inputting datastored in the magnetic strip of credit cards, and/or an electronic smartcard reader for inputting data stored within smart cards.

The input data is collected and formatted into a request by the LHTD andthen is generally transmitted to a server computer through thetelecommunications link. The server computer carries out one or moreoperations corresponding to the request, collects any informationobtained or retrieved as a result of the operations, and returns theinformation as a response to the LHTD, transmitted from the servercomputer to the LHTD over the telecommunications link. The LHTD thendirects portions of the response to appropriate data output componentsthat output data of different types. For example, a LHTD commonlycontains a low power display, such as a liquid crystal display (“LCD”),that displays text-based and graphical information and an audio speakerfor outputting audio data, including voice data. Additional types ofdata output components may be included in a LHTD, including a printercomponent.

In order to provide maximum convenience and availability to a user, theLHTD draws sufficient electrical power from the telecommunications link(telephone line loop current, batteries, or computer port to which it isconnected) to input data, transmit requests over the telecommunicationslink, receive responses to the requests from the telecommunicationslink, and output the responses. The LHTD carefully manages powerconsumption by the various data input, data transfer, and data outputcomponents within the LHTD in order to operate on the relatively meagerelectrical energy supply provided by the telecommunications line orbatteries. The components are generally maintained in inactive statesand are only activated when needed to perform their respectivefunctions. For example, communications between the LHTD and a servercomputer may follow a request/response paradigm, and components withinthe LHTD may need not be continuously maintained in an active state inorder to field communications from the server computer, but can,instead, be activated only for the time required to send a request andreceive a response to that request. The LHTD, when connected to a wiredor wireless telecommunications link, may also be used to send andreceive analog signals through the telecommunications link and thusoperate as an ordinary telephone. The LHTD may also transmit and receivevoice data encoded as digitized packets and thus operate as a digitaltelephone. The LHTD enables person-to-person voice communications aswell as bi-directional voice communications with a server. The servermay record voice messages or recognize voice messages as commands. Theserver may also enable live communications between the LHTD user andanother person, such as a merchant employee.

The LHTD may apply data compression to the encoded voice data byapplying one of a number of standard compression algorithms. When datacompression is applied, the number of digitized packets transmitted fora given period of voice data input can be significantly decreased,increasing the data transmission rate and significantly decreasing theamount of power required to operate the transceiver. Data compression ofdigitally encoded voice data is thus a significant component of thepower management strategy.

In order to be effectively used as a secure transaction device, the LHTDmay provide for secure storage of confidential information, includingcredit card numbers. The LHTD may include a protected memory withrestricted access to devices external to the LHTD. Credit card numbersread by a magnetic credit card reading component may be stored withinthe protected memory and may be transmitted as part of a request afterbeing encrypted within the LHTD prior to transmission to thetelecommunications link.

FIG. 1 is a high-level block diagram of the LHTD. A low-powermicroprocessor 102 included in the LHTD 100 executes firmware routines(not shown) that coordinate operation of the input, output, andtransceiver components of the LHTD 100. The microprocessor 102 maycontain a protected memory 104 that is used to store confidentialinformation, such as credit card numbers. This protected memory 104 canbe written to and read from by the firmware routines that execute withinthe microprocessor 102. Attempts to read the contents of a location ofprotected memory 104 by an external device or by a software routineother than a firmware routine may result in erasing the values in anyprotected memory locations accessed, without returning the values to theexternal device or software routine. This protected memory isnonvolatile, the contents surviving power-down and power-up cycles. Themicroprocessor may also include non-protected nonvolatile memory, orseparate non-protected nonvolatile memories may be included. Nonvolatilememory can store requests for subsequent transmission. The LHTD 100transmits and receives information to and from the telecommunicationslink (not shown) via output signal line 106 and input signal line 108,respectively. Output signal line 106 and input signal line 108 transmitdigital signals which may be, as discussed below, converted to and fromanalog signals that are transmitted over the telecommunications link.

The LHTD 100 includes a visual display component 110 for output ofalphanumeric symbols, including text-based data, and for output ofgraphical images. The visual display 110 is commonly a LCD. Data to beoutput is transmitted in digital form from the microprocessor 102 to thevisual display device 110 through a digital signal line 112. The LHTDincludes a keypad 114 that enables mechanical input of alphanumericsymbols through a digital-signal line 116 to the microprocessor 102. TheLHTD may include additional input and output devices, collectivelydepicted in FIG. 1 as device 118 connected to the microprocessor 102 bythe digital signal line 120. These additional input and output devicesmay include a barcode reader, a magnetic card reader, an electronicsmart card reader, and a printer. Audio data, including voice data, isinput to the LHTD through a microphone 122 that outputs an analog signalvia an analog signal path 124 to an amplifier 126. The amplifier 126amplifies the analog signal and sends the amplified analog signalthrough a signal path 128 to a codec component 130 that converts theamplified analog signal to a digital signal that is directed to themicroprocessor 102 through a digital signal line 132. Audio data,including voice data, received from the telecommunications link viadigital input 108, is processed by the microprocessor 102, transmittedto the codec device 130 via the digital signal line 132, converted to ananalog signal by the codec component 130, and output by the codeccomponent 130, via an analog signal line 134, to an amplifier 136. Theamplifier 136 amplifies the analog signal and passes the amplifiedanalog signal, via analog signal path 138, to the audio speaker 140 foroutput.

Certain DSP chips have microprocessors with sufficient processingability to perform may of the functions of an LHTD, including decodingbar code signals, encrypting and decrypting data, communicating voiceand data to a host server, and executing the power management and powerconservation communication protocols. Some DSPs have A-to-Ds and D-to-Ascapable of implementing codecs and modems used in an LHTD. An LHTDemploying such DSP chips is considered to fall within the scope andspirit of the present invention.

Power is an important issue in LHTD design. Wireless telephone serviceproviders wish to maximize user services by maximizing wireless phonebattery life. Low current draw also encourages use of convenient smallphone batteries. Phone lines provide very limited current to operate theLHTD, thus wired LHTDs also require power management.

The LHTD employs careful power management strategies and low-powerinternal components in order to conserve sufficient electrical energy tooperate the various components shown on FIG. 1. For example, amplifiers126 and 136 may be dual-power mode amplifiers, discussed in detailbelow. These amplifiers draw very little current when there is no inputsignal to be amplified. Upon input of an input signal, a dual-power modeamplifier transitions to a high-power state in which the amplifier drawssignificant amounts of current in order to boost the voltage of theoutput signal. Thus, dual-power mode amplifiers draw significant currentonly when necessary.

As another example, device 118 may represent a barcode reader.Conventional barcode readers draw relatively large amounts of electricalpower in order to operate an internal microprocessor, a light source(not shown), and an image sensor that collectively illuminate a targetbarcode and read the barcode via reflected light. Continuous operationof the barcode reader, even when the barcode reader is only activated bya push button trigger, may quickly deplete the electrical energyavailable to the LHTD. By careful design of communication protocols, thelow power barcode reader 118 included in the LHTD 100 may be activatedin a low-power state until it is needed, and is only then fullyactivated to a high-power state in order to read the barcode andtransmit the barcode through the digital signal line 120 to themicroprocessor 102. The LHTD may optionally use a low power laser, CCD,LED, optical, electrical, or magnetic readers.

When no data is being input to the LHTD 100, and when no responses areexpected by the LHTD 100 from the telecommunications link, components ofthe LHTD 100 may be maintained in inactive states in order to conserveelectrical power. The microprocessor 102 may include an internal timer(not shown) that can be set to awaken the microprocessor 102 at somepre-selected time interval so that the microprocessor can suspendprocessing when there are no immediate processing tasks at hand. As yetanother alternative, a multi-speed microprocessor can be used as theLHTD microprocessor 102. When there are no processing tasks, the clockrate of the multi-speed microprocessor can be lowered to conserve power,and when a processing task becomes available, the clock rate of themulti-speed processor can be raised to provide sufficient processingpower to efficiently complete the processing task. Multi-speedprocessors commonly operate at clock rates from 32 kHz to about 40 MHzor more. The LHTD may save power and hardware costs by sharing amicroprocessor and other components with wired or wireless telephonecircuitry.

By careful conservation of electrical power, the LHTD 100 can provide alarge assortment of input and output devices with power. These devicesmay not be simultaneously operated under the electrical powerconstraints imposed by the small amount of electrical power availablefrom the telecommunications link loop current or may cause excessivebattery drain. LHTD components are activated and maintained in ahigh-power state only as long as necessary to complete a task.

FIG. 2 is a schematic diagram of a dual-power mode amplifier. The signalto be amplified is input on signal line 202 to the dual-power modeamplifier 200. A reference signal line is input to the dual-power modeamplifier 200 on input line 204. The amplified signal is output onoutput signal line 206. When the voltage differential between the inputsignal on line 202 and the reference signal on line 204 is less than athreshold value, the dual-power mode amplifier remains in a low-powerstate, drawing little or no current from the power supply (not shown)and producing no output signal. When, however, the voltage differentialbetween the input signal on line 202 and the reference signal on line204 exceeds the threshold value, the dual-power mode amplifier 200transitions to a high-power state in which the dual-power mode amplifier200 draws current from the power supply and produces an amplified signalon output line 206. Resistors 208 and 210 together set the gain for theamplifier, where the gain is the ratio of the resistance of resistor 208divided by the resistance of resistor 210. The dual-power mode amplifier200 has a fixed threshold voltage for the low power to high-powertransition. The gain is set to provide a desired output voltage fromrelatively low-voltage input signals while allowing a reasonable levelof discrimination based on the threshold voltage differential for thedual-power mode amplifier 200. By using dual-power mode amplifiers foramplifying signals input to the data input components of the LHTD, thedata input components draw significant current only when input is beingtransmitted to them.

FIG. 3 is a block diagram of a LHTD coupled to a standard telephoneline. FIG. 3 shows many of the same components of the LHTD as shown inFIG. 1. The components of the LHTD that are shown in FIG. 3 as well asin FIG. 1 are labeled, in FIG. 3, with the same numerical labels withwhich the components are labeled in FIG. 1. In the interest of brevity,descriptions of those components of FIG. 3 also shown in FIG. 1 will notbe repeated.

Current flows from the telephone line into the LHTD 300 via the tipinput 302 and returns to the telephone line via the ring output 304. Theinput current from the telephone line passes to the ring sensor 306,which detects and responds to the relatively high-voltage alternatingcurrent (“ac”) signal that is transmitted through the telecommunicationslink to notify a receiving device, such as the LHTD, of an incomingtelephone call. The ring sensor 306 may optionally direct currentderived from the incoming ring signal to the power supply 308 via acsignal line 310. The user may also activate the power supply 308 byactivating an “off hook switch.” The power supply 308, may, in turn,awaken the microprocessor and power it to begin processing the call. Aspart of its initial processing, the microprocessor 102 sends a SETsignal via signal line 312 to a relay 314. The relay 314 acts as aswitch that is closed, or activated, by the SET signal. When relay 314is activated by the SET signal, the relay 314 passes the current fromthe telecommunications link via signal path 316 to a line coupler 318,commonly a transformer. The line coupler 318 extracts the ac signal fromthe current input from the telephone line and passes the extracted acsignal through ac signal line 320 to an amplifier and mixer 322. Theline coupler 318 passes the direct current (“dc”) component of thecurrent input from the telephone line via signal line 324 to the powersupply 308, which rectifies and regulates the current and provides astable dc output on output signal line 326 relative to ground 328. Theamplifier and mixer 322, including a dual-power mode amplifier describedabove and shown in FIG. 2, amplifies the incoming ac signal from the acsignal line 320 and passes the amplified signal to output signal lines330 and 332. Output signal line 330 passes the amplified ac signal tothe transceiver 334. Output signal line 332 passes the amplified accurrent through a switch 336 and ac line 338 to amplifier 136, adual-power mode amplifier that outputs a sufficiently high-voltagecurrent via output signal line 138 to drive the audio speaker 140. Thesignal branch effected by the mixer component of the amplifier and mixer322 may allow analog telephone signals to be routed directly to theaudio speaker 140, whereas digitized signals are passed to transceiver334 which converts the analog signal input via ac line 330 to a digitalsignal that is passed from the transceiver 334 to the microprocessor 102via signal line 346.

Firmware routines running within the microprocessor 102 control whethercommunications are conducted by analog signals or by digitized signals.These firmware routines activate and deactivate switches, such as switch336, to direct communication signals to appropriate signal processingcomponents. The communications protocols used by the LHTD arerequest/response protocols, and may anticipate whether a response willbe communicated and received as an analog signal or as a digitizedsignal. Therefore, the transceiver 334 is activated by a signal sentfrom the microprocessor 102 for digitized communications. Thetransceiver may not need to be continuously active in order to monitorthe input signal of line 330 for unexpected and unrequestedtransmissions. Thus, the request/response paradigm, communicationsprotocols that may be used by the LHTD, allow for significant power andtime conservation. Minimizing the time during which components in theLHTD are active enables timesharing of components, such as themicroprocessor, codec, and transceivers, between multimedia order-entryand telephone circuitry. By careful design of hardware and protocols,component activation and deactivation is not apparent to the user.

In addition to the transceiver 334, the LHTD may include a multiplefrequency (“MF”) or a dual-tone multiple frequency (“DTMF”) tonegenerator (not shown) to generate analog control signals that do notoccur in speech, music, or modem communications. DTMF tones may be sent,for example, by the LHTD to interrupt analog voice data transmissionssent from a remote transceiving device so that a request can beimmediately sent in digitized form by the LHTD to the remotetransceiving device. In this case, the DTMF tone is used, essentially,as an interrupt signal. DTMF tones can also be used for initialnegotiations between the transceiver 334 of the LHTD and a remotetransceiver (not shown). Various transmission parameters, such as baudrate, are normally exchanged between two transceivers, and mutuallyacceptable parameters are agreed upon by the transceivers during anegotiation process that may last on the order of tens of seconds. Byinstead encoding the transmission parameters as DTMF signals, the LHTDcan effect an extremely fast connection to a remote transceiving devicecapable of receiving and interpreting the DTMF signals. The DTMFgenerator may also be used to dial telephone numbers.

The LHTD may optionally support analog or digital audio communications.The LHTD may optionally support both analog and digital voicecommunications.

As described above, incoming analog signals may be routed by the mixercomponent of the amplifier and mixer 322 to the audio speaker 140 foroutput. Audio tones, including voice data, input to the LHTD throughmicrophone 122 are passed through a signal line 124 to the dual-powermode amplifier 126, which amplifies the audio signal and, when switch354 is closed, outputs the amplified ac audio signal through signallines 356, 358, and 360 to the amplifier and mixer 322. The amplified acsignal is then directed through signal line 362 to line coupler 318 andback to the telecommunications link. The LHTD may, when switches 336 and354 are both closed, operate as a standard telephone, transmittinganalog signals input through the microphone 122 to thetelecommunications link and receiving analog signals from thetelecommunications link and passing those signals to audio speaker 140.

The LHTD may support digital voice communications. In this form oftelecommunications, analog voice signals are digitized and placed intodigital packets that are transmitted over the telecommunications link. Adigitized voice data packet is received from the telecommunications linkby the transceiver 334 and converted into a digital signal transmittedvia digital signal line 346 to microprocessor 102. The microprocessorprocesses the digital signal to extract the digital voice signal andpasses the digital voice signal over digital signal line 132 to thecodec 130. The codec 130 is a digital-to-analog and analog-to-digitalconverter. The digital voice signal is converted by the codec 130 to ananalog voice signal that the codec outputs via analog signal line 368,switch 370, and analog signal line 372 to amplifier 136 for output tospeaker 140. Voice input to the LHTD through microphone 122 is amplifiedby amplifier 126 and passed through analog signal lines 356, switch 374,and analog signal line 376 to the codec 130, where the analog signal isconverted into a digital signal and directed through digital signal line132 to microprocessor 102. The microprocessor then packages the digitalvoice signal into a digitized packet and outputs that packet via digitalsignal line 378 to transceiver 334. The transceiver then transmits thedigitized packet to the telecommunications link. Digitized packets canalso be used for encoding and transmitting audio signals for music andnon-voice audio tones.

Transceiver 334 provides the LHTD with bi-directional communications viathe telecommunications link. Bi-directional communications enable theexchange of encryption parameters and sequence numbers between the LHTDand the remote server computer prior to transmission of data. Thus,bidirectional communications make highly secure data transfers from theLHTDF to a remote server computer possible.

FIG. 4 is a more detailed block diagram of the ring sensor, relay, andpower supply components of the LHTD shown in FIG. 3. The features shownin FIG. 4 that are also shown in previous figures are labeled in FIG. 4with the same numerical labels with which they are labeled in previousfigures. In the interest of brevity, descriptions of these features willnot be repeated below.

The optional ring sensor 306 or the user pressing switch 420 enables theline powered LHTD to answer an incoming call. The optional ring sensor306 comprises a resistor 402 and capacitor 404. The capacitor 404 servesto block dc and pass only ac. A Zener diode 406 clamps the telephoneline voltage to a maximum potential, such as 10V. Thus, the ring sensorresponds to a ring signal transmitted through the telecommunicationslink, normally with an average voltage in excess of 150 volts, bydirecting ac current through an ac signal line 310 to the power supply308. The power supply comprises a bridge rectifier 408 and voltageregulators 412. Incoming ac from the ring sensor input through ac signalline 310 is processed by the bridge rectifier to produce positivevoltage at output 409. The bridge rectifier compensates for reversepolarity of the telecommunications link. The positive voltage outputfrom the bridge rectifier is output as dc through signal line 410 to thevoltage regulators 412. The voltage regulators process the dc from thebridge rectifier to produce a constant-voltage dc output on outputsignal line 326. If the incoming dc is insufficient to produce theconstant-voltage dc output, a low battery output (“LBO”) signal istransmitted from the voltage regulators 412 over the LBO signal line 414to the microprocessor 102. This causes the microprocessor to pause for ashort time interval and to then restart and test the LBO signal, waitinguntil sufficient power is available to begin processing an incomingcall. As discussed above, the relay 314 acts as a switch. When theswitch is open, or deactivated, no current is passed from thetelecommunications link through the relay 314 and through signal line316 to line coupler 318. When the relay is closed, or activated, currentis passed from the telecommunications link through the relay 314 andsignal line 316 to the line coupler 318. As discussed above, the relay314 is activated by a SET pulse signal from microprocessor 102 inputthrough the signal line 312 and is deactivated by a RESET pulse signalfrom the microprocessor 102 input to relay 314 through input 313. Themicroprocessor 102 is awakened from sleep mode or, in other words,reset, when voltage is output from the power supply 412 to the voltageoutput 326. Thus, an incoming ring signal is passed through the ringsensor 306 to the power supply 308 and, finally, as a constant voltageto the microprocessor 102. Upon awakening, the microprocessor 102 sendsa SET signal to the relay 314, activating the relay 314 and allowingcurrent to pass through the line coupler 318.

When the relay is activated, and current is passing from thetelecommunications link to the power supply 308, current also passes viasignal line 410 back to the relay 314 and through signal line 416 to acapacitor 418. This capacitor 418 is able to store energy obtained fromthe telecommunications link for later use. A battery can be used inplace of capacitor 418 in order to save greater amounts of electricalenergy. The energy stored in capacitor 418 can be used to operate theLHTD when the LHTD is not connected to a telecommunications link. Theenergy stored in capacitor 418 can also be used to activatemicroprocessor 102 in response to input from a user of the LHTD. Whenthe LHTD is activated by push button 420, current is drawn fromcapacitor 418 and the telecommunications link through signal line 410 tothe voltage regulator 412, which outputs the current on output 326. Whenthe power supply is thus activated to output a constant voltage, themicroprocessor 102 is awakened and sends a SET signal to activate therelay 314. Once the relay 314 is activated by the SET signal, the LHTDcontinuously draws current from the telecommunications link via tipinput 302, relay 314, and signal line 410 to the voltage regulator 412.

Because the current available from a telephone line may be inadequate topower the components of the LHTD, the power supply 308 preferablyemploys a step-down switching regulator 412. This type of voltageregulator decreases the voltage supplied by a telecommunications linkand correspondingly increases the current. As a result, the step-downswitching voltage regulator generates a constant 5V, 3V, or both 5V and3V outputs, or other voltages depending on the voltage requirements ofcomponents used within a particular embodiment of the LHTD, w The LHTDmay be connected to input or output components via a serial port such asRS232. The LHTD may draw power from the serial port. In someapplications, such as interfacing to battery power devices, the LHTD maynot draw power from the RS232 port. In these cases, the LHTD will bepowered by a battery or telephone loop current.

The LHTD may be coupled to a local computer via an RS232 connection or aUSB connection. A USB connector has a power pin that may provide powerto the LHTD. The local computer is, in turn, connected to a remoteserver computer via a telecommunications link. When coupled to a localcomputer via an RS232 connection, the LHTD sends and transmits digitalcommunication signals through the RS232 and, as in the case of atelephone line connection, derives sufficient electrical power from theRS232 connection to power the internal components of the LHTD.

FIG. 5 is a block diagram of the LHTD coupled to a computer through anRS232 connection. The components shown in FIG. 5 that are also shown inprevious figures are labeled with the same numerical labels with whichthe components are labeled in the previous figures. In the interest ofbrevity, descriptions of these components will not be repeated.

Incoming signal lines from the RS232 connection include the dataterminal ready (“DTR”) signal line 502, the ready to send (“RTS”) signalline 504, and the receive (“RXD”) signal line 506. Each of these inputsignal lines 502, 504, and 506 branches in order to enter both the RS232receiver 508 as well as the power supply 510. The RS232 receiver 508transforms the input signals into positive voltage digital signals andpasses the digital signals to the microprocessor 102 via digital signallines 512, 514, and 516. When the LHTD transmits communications data viathe RS232 connection, the microprocessor 102 sends digital signalsthrough the digital signal output line 106 to the RS232 driver 518,which, outputs the digital signals through the RS232 transmit signalline (“TXD”) 520. Additional handshake (“HS”) signals 522 aretransmitted from the LHTD to the RS232 connection. In this applicationthe LHTD uses the HS signals for both data transmission orcommunications synchronization and as a power source.

FIG. 6 is a block diagram of the power supply used when the LHTD iscoupled to an RS232 connection. This specialized power supply is able todraw constant positive voltage from the RS232 connection, regardless ofthe polarity of the incoming signal lines. The components shown in FIG.6 that are also shown in previous figures are labeled with the samenumerical labels used in the previous figures. In the interest ofbrevity, descriptions of these components will not be repeated.

When the incoming DTR 502 and RTS 504 signal lines have positivevoltage, current passes through diodes 602 and 604 through signal line606 to a capacitor 430 and voltage regulator 412. However, when thepolarity of signal line DTR 502 and RTS 504 are reversed, current fromsignal lines DTR 502 and RTS 504, as well as current from signal lineRXD 506, flows through diodes 608, 610, and 612, respectively, tocapacitor 614. The negative charge stored in capacitor 614 flows throughcharge pump 616 and is output via signal path 618 to capacitor 430 andvoltage regulator 412. Charge pump 616 transforms input current withnegative voltage to an output current with positive voltage. Capacitors614 and 430 store electrical energy obtained from the RS232 connectionand release that electrical energy to the voltage regulator 412, whichproduces a constant output voltage on output signal line 326. Wheninsufficient electrical power is available from the RS232 connection,and the capacitors are depleted, the voltage regulator outputs a LBOsignal 414 to microprocessor 102. In response to the LBO signal,microprocessor 102 coordinates the transition of the internal componentsof the LHTD, including microprocessor 102, to sleep states untilsufficient electrical power is available to power their operation.Capacitor 430 is essentially a buffer, smoothing out small interruptionsin the availability of electrical power from the RS232 line. Undernormal conditions, the power supply settles into a steady state andproduces a constant voltage output.

In one embodiment, the LHTD may be coupled both to a local computer viaan RS232 or USB link and, at the same time, to a telecommunicationslink. Because the voltage supplied by the former link is positive withrespect to ground, and the voltage supplied by the latter link isnegative with respect to ground, the LHTD, in this embodiment, requiresoptical coupling, level shifting, or other type of coupling in order todraw current from both types of links.

FIG. 7 is a block diagram of one embodiment of a low-power consumingbarcode reader. Common barcode readers consume more electrical energythan is available to the LHTD through a telecommunications link.Consequently, a low-power barcode reader embodying careful powermanagement strategies is included in one embodiment of the LHTD. Anexample of one low-power barcode reader 700 illuminates LEDs within in abank of LEDs 702 in order to illuminate a target barcode 704. Theemitted light produces a concentrated, horizontal beam 706 across thetarget barcode 704. A portion of the beam 706 is reflected back to thebarcode reader 708 and focused by an optical element 710. The focusedlight then falls unto the window 712 of a CCD or CMOS image sensor 714that generates electrical signals corresponding to the patterns of lightand dark bands reflected from the target barcode 704. The electricalsignals from the CCD or CMOS image sensor 714 are then output throughsignal line 716 to signal conditioner 718, which outputs, via outputline 720, a digital signal to the microprocessor 102 that corresponds tothe barcode. The low-power barcode reader can be activated by pressing apush button trigger 722. Activation of the push button trigger 722awakens a low-power microprocessor 724 within the low-power barcodereader 700. The low-power microprocessor 724 illuminates a small numberof centrally positioned LEDs 726 within the bank of LEDs 702 via signalline 728 and illuminates the other LEDs within the bank of LEDs 702 viasignal line 730. The low-power microprocessor 724 includes a timer 732.The low-power microprocessor 724 receives digital signals from thesignal conditioner 718, via digital signal line 734, and sends digitalsignals to the microprocessor 102, via digital signal output line 736.

Illuminating the majority of LEDs within the bank of LEDs 702 draws acomparatively large amount of current. This comparatively large numberof LEDs may not be continuously operated from the electrical powerobtained from a telecommunications link. Instead, the power managementstrategy incorporated in the low-power barcode reader attempts to avoidactivating the majority of LEDs within the bank of LEDs 702 until atarget barcode 704 is sufficiently well positioned with respect to theposition of the light beam 706 to enable a reliable reading of thetarget barcode 704. When the push button trigger 722 is pushed, thelow-power microprocessor 724 is awakened and sends a signal throughsignal line 728 to activate the small number of centralized LEDs 726that together comprise a proximity detector. Illuminating only a few ofthe LEDs within the bank of LEDs 702 draws much less current and enablesthe LHTD to operate for longer periods under the power constraintsimposed by the telecommunications link. The proximity detector LEDs 726produce, in addition, a much smaller beam of light 706, which has theadded advantage of serving as an optical pointing device to properlycenter the target barcode for reflecting light into the optical element710.

The low-power microprocessor 724 activates the CCD 714 via signal line738 to process reflected light from the proximity detector 726,monitoring the output 734 of the signal conditioner 718 to determinewhether sufficient reflected light energy is available to take a barcodereading. If insufficient reflected light is available, themicroprocessor returns to a sleep state after setting timer 732 andreawakens to again monitor output of the signal conditioner 718. Thus,the low-power microprocessor 724 need not operate continuously duringthe course of target barcode acquisition. When sufficient reflectedlight is available, the low-power microprocessor 724 causes the majorityof LEDs within the bank of LEDs 702 to be illuminated to produce asufficiently strong beam 706 to make a barcode reading. Output from thesignal conditioner 718 as a result of illumination of the majority ofthe LEDs within the bank of LEDs 702 is passed by the low-powermicroprocessor 724 to the LHTD microprocessor 102 after the low-powermicroprocessor 724 first awakens the LHTD microprocessor 102. The LHTDmicroprocessor 102 then processes the digital signal from the signalconditioner 718. If a barcode is successfully read by the LHTDmicroprocessor 102, then the LHTD microprocessor 102 prepares a requestbased on the barcode and sends the request to a server computer over thetelecommunications link. If, on the other hand, a barcode is notsuccessfully read, then the LHTD microprocessor 102 returns to a sleepstate, the bank of LEDs 702 is turned off, and the entire process oftarget acquisition via the proximity detector can be repeated. Thus, thelow-power barcode reader conserves comparatively large amounts ofelectrical energy in comparison to a standard barcode reader byilluminating the majority of LEDs within the bank of LEDs 702 only whenthe chance for successfully reading a barcode is high, activating theLHTD microprocessor 102 only when a sufficiently strong signal isavailable from the signal conditioner 718. The low-power microprocessor724 may even cursorily analyze the output from the signal conditioner718 to determine whether a sufficient number of light and dark regionsare present to indicate a barcode prior to waking up the LHTDmicroprocessor 102. In an alternate embodiment, the low-powermicroprocessor 724 may interpret the barcode, rather than pass thesignal from the signal conditioner 718 to the LHTD microprocessor 102.Alternate embodiments of the low-power barcode reader employ a separateproximity detector, rather than selectively illuminating a small numberof LEDs 726 within the bank of LEDs 702. Alternate embodiments of a CCDbar code scanner may achieve the requirements of a low power CCD scannerwithout a proximity detector. These embodiments include strobing thelight source and other techniques to manage power requirements.Alternate embodiments of the low-power bar code reader may includesingle point LED readers, low-power CCD readers or low power laserreaders.

FIG. 8 is a block diagram of the LHTD connected to a cellular/PCStelephone. The components shown in FIG. 8 that are shown in previousfigures are labeled with the same numerical labels with which they arelabeled in the previous figures. In the interest of brevity,descriptions of these components will not be repeated.

When a LHTD is connected to a cellular telephone or a PCS telephone,either type of telephone referred to below as a “cellular” telephone,the LHTD may not require a visual display device, a keypad, a microphoneor a speaker, since the LHTD can make use of the visual display, keypad,microphone, and speaker included in the cellular telephone. In addition,the LHTD may obtain electrical power through the accessory connector ofthe cellular telephone. In the case of a cellular telephone that exportsdigital signals, the LHTD may not require a separate modem. In yetanother embodiment, the microprocessor of the LHTD may be used toprovide processing capabilities to the cellular telephone so that thecellular telephone need not include a separate microprocessor.

The LHTD embodiment 800 shown in FIG. 8 receives digital input signals802 from the cellular telephone and transmits digital signals 804 to thecellular telephone. These digital signals enable the LHTD to control thevisual display of the cellular telephone and to intercept and respond tokeypad-initiated signals from the cellular telephone. In fact, each keyand display element of the cellular telephone may be separatelymanipulated by specific commands transmitted from the microprocessor ofthe LHTD 102 through digital output 804. The LHTD receives analogsignals from the cellular telephone through analog output 808 andreturns analog signals to the cellular telephone through analog input806. These analog signals correspond to normal telephone analog signalsand are processed by the LHTD just as the telephone signals in FIG. 3are processed by the embodiment of the LHTD shown in FIG. 3. The powersupply 308 for the LHTD obtains electrical power from the accessory port810 of the cellular telephone, regulates the supplied current, andoutputs a constant voltage via power output 812. In this embodiment, theLHTD relies on the cellular telephone to send and receive signals for atelecommunications link. In an alternate embodiment, the communicationsignals 806 and 808 may be supplied and received as digital signalsrather than analog signals. In the alternate embodiment, amplifier 322and transceiver 334 would not be needed, but a codec would be requiredfor digital/analog conversion.

FIGS. 9-13 are flow control diagrams that describe the firmware routinesexecuted by the LHTD microprocessor 102. FIG. 9 is a flow controldiagram for the main firmware routine. The firmware routine “main”begins executing when the LHTD microprocessor 102 is powered up by, forexample, depressing pushbutton 420 in FIG. 4. The firmware routine“main” begins executing at step 902. In step 902, main sends a SETsignal to relay 314 in order to activate the relay to begin drawingcurrent from the telecommunications link. In step 904, main sets a timerto reawaken itself in the event that main enters a sleep mode in step908, below. In step 906, main tests the LBO signal to determine whethera dependable power supply is now being generated by the power supply308. If main determines that the power supply is not yet sufficient tooperate the components of the LHTD, in step 907, control flows to step908, in which main enters a sleep mode and is eventually reawakened bythe timer set in step 904. Once reawakened, main begins executing againat step 904. If main determines that the power is sufficient then, instep 907, main initializes all the components within the LHTD in theloop represented by steps 910, 912, and 914. In step 916, maindetermines whether there is any request data stored in nonvolatilememory. If there is request data stored in nonvolatile memory, then instep 918, main retrieves the request data from nonvolatile memory,formats the request data into one or more requests, opens communicationswith a remote server over the telecommunications link, ensures that thecommunications connection with the remote server is secure, and thensends the formatted requests and receives the appropriate responses fromthe server computer and displays them. This access of stored requestdata and execution of transactions based on the stored request data insteps 916 and 918 allow the LHTD to be used, off line, to input requestdata and store the request data for subsequent use. If, in step 918, aconnection cannot be established through the telecommunications link tothe remote server, then the request data continues to be stored innonvolatile storage until a later time. Finally, in step 920, mainexecutes the firmware routine “process_input” to begin processing inputto the LHTD.

FIG. 10 is a flow control diagram for the firmware routine“process_input.” The firmware routine “process_input” basicallydetermines the nature of the input data that will be input to the LHTDand calls an appropriate firmware routine to handle that type of inputdata. If process_input determines, in step 1002, that a user isinputting a telephone number through the keypad, then process_inputcalls the firmware routine “telephone_input,” in step 1004, to establisha point-to-point telephone link in accordance with the user's request.If, on the other hand, process-input determines in step 1006 that theuser has input an indication to go on-line and send requests based onrequest data input through one of the input components of the LHTD, thenprocess_input calls the firmware routine “on-line request” in step 1008.Alternatively, if process_input determines, in step 1010, that the userhas activated one of the input components directly in order to inputrequest data that will be stored in memory, i.e., the user desires touse the LHTD off-line, then, in step 1012, process_input calls thefirmware routine “off-line_request.” If none of this type of input hasbeen made available to the LHTD, then, in step 1014, process_input sendsa RESET signal to relay 314 to deactivate the relay and then returns, instep 1016. In this later case, the LHTD microprocessor 102 will bepowered down.

FIG. 11 is a flow control diagram for the firmware routine“telephone_input.” In step 1102, telephone_input sets the analogswitches 336, 354, 370, and 374 of FIG. 3 in order to configure the LHTDfor use as a telephone. In step 1104, telephone_input enables the DTMFtone generator, discussed above. Then, in step 1106, telephone_inputsets a timer and enters a wait state. After awakening, telephone_input,in step 1108, determines whether it was awakened by keypad input of adigit. If so, then, in step 1110, telephone_input sends a DTMF tonecorresponding to the input digit to a telecommunications link andreturns to step 1106. If not, then, in step 1112, telephone_inputdetermines if the user has input an off-line indication to discontinuethe telephone call. If so, then control flows to step 1116. Otherwise,in step 1114, telephone_input determines whether a telephone connectionis still open to a remote telephone. If so, then the telephone call hasnot yet been completed, and control flows back to step 1106. Otherwise,telephone_input sends a RESET signal to relay 314 in step 1116, whichpowers down the LHTD and returns.

FIG. 12 is a flow control diagram of the firmware routine“online_request.” In step 1202, on-line_request establishes atelecommunications connection to a remote server. This may occur in anumber of different ways. In one embodiment, on-line_request mayretrieve a telephone number or other communications address for theremote server, dial the telephone number, and wait for establishment ofa connection between transceiver 322 and the remote transceiver of theremote server computer. Alternatively, on-line_request might cause thevisual display of the LHTD to indicate to the user that a connectionaddress must be provided, input that connection address from the keypador barcode reader, and use that input address in order to connect to theremote server. Once a telecommunications connection has been establishedwith the remote server, then, in step 1204, on-line_request determineswhether a secure communications link needs to be established. Thisdetermination may be made from stored configuration information or maybe determined by querying the user. If a secure communications link isto be established, then, in step 1206, on-line_request establishes thissecure connection through a security handshake mechanism that mayinvolve the exchange of sequence numbers and other messages between theLHTD and the server computer. In step 1208, on-line_request determineswhether a secure connection was established. If so, the control flows tostep 1212. If a secure communications link has not been established,control flows to step 1210, in which on-line_request alerts the userthrough an output component such as a visual display that a securecommunications link was not established and control flows to step 1224.

If a secure communications link has been established, or when no securecommunications link was necessary, on-line_request sets a timer in step1212 and enters a wait state in step 1214. When on-line_request isawakened, then, in step 1216, on-line_request determines whether requestdata has been received from an input component, such as the barcodereader. If so, then, in step 1218, on-line_request formats the inputrequest data into a request, sends that request to the remote server,waits for the response, and displays the response on one or more of theoutput components of the LHTD. Once the response has been displayed,control flows back to step 1212. Note that, during reception of theresponse from the remote server in 1218, a user may depress a button orotherwise indicate a desire to interrupt the response from the servercomputer in order to initiate a new transaction or initiate apoint-to-point telephone call with a human operator. In the former case,step 1218 may be prematurely terminated, after which control flows backto step 1212. In the later case, a telephone connection can beestablished, such as in firmware routine “telephone_input,” describedabove. If request data has not been received when on-line_request isawakened from the wait state entered in step 1214, then, in step 1220,on-line_request sends a sign off message to the server computer, and, instep 1222, conducts any end of session maintenance necessary, includingstoring information in nonvolatile memory, sends a RESET signal to relay314, in step 1224, and returns. Microprocessor 102 is then powered downand executes no further firmware.

FIG. 13 is a flow control diagram for the firmware routine“off-line_request.” In step 1302, off-line_request sets a timer andthen, in step 1304, enters a wait state. When off-line_request isawakened from the wait state, it checks, in step 1306, whether anyrequest data has been received from an input component of the LHTD. Ifrequest data has been received, then, in step 1308, off-line_requeststores the request data input in nonvolatile memory and returns to step1302 to await for additional request data. If, upon awakening from thewait state entered in step 1304, off-line_request determines that norequest data has been received, then, in step 1310, off-line_requestsends a RESET signal to line 314 to power down the LHTD, and returns.

The firmware routines may be implemented in many different ways.Different numbers of firmware routines may be used, and a differentcontrol flow and different steps may be employed. The above-describedfirmware routines represent a preferred embodiment. Additionalfunctionality provided by the LHTD may require enhancement of, andadditions to, the firmware routines.

FIGS. 14-30 together display more detailed block and circuit diagrams ofthe internal components of various embodiments of the LHTD. FIG. 14illustrates the external appearance of one embodiment of the LHTD. FIG.15 is a detailed block diagram of an embodiment of a LHTD designed forconnection to a telephone line. FIG. 16 is a circuit diagram for thetelephone interface and power supply for the LHTD shown in FIG. 15. FIG.17 is a circuit diagram for the LHTD described by the block diagram ofFIG. 15. FIG. 18 is a circuit diagram for a LHTD designed to beconnected to a cellular of PCS telephone. FIG. 19 is a circuit diagramfor a LHTD designed to be connected to a wireless telephone. FIG. 20 isa block diagram for a two-unit LHTD designed for connection to acordless telephone. FIG. 21 is a block diagram for a wireless two-unitLHTD designed for connection to a personal computer. FIG. 22 is a blockdiagram for a barcode reader with a separate proximity detector. FIG. 23is a block diagram for a LHTD communicating with and powered by a serialport. FIG. 24 is a circuit diagram for a signal conditioner included ina barcode reader. FIG. 25 is a block diagram for a smart card interfacethat may be included in a LHTD. FIG. 26 is a circuit diagram for amagnetic card reader that may be included in a LHTD. FIG. 27 is acircuit diagram for an alternate embodiment of a power supply for a LHTDdesigned for connection to a telephone line. FIG. 28 is a circuitdiagram for a serial port power supply. FIG. 29 is a block diagram for aLHTD specially designed for digital voice communications. FIG. 30 is acircuit diagram for a modem interface to a voice and data mixer includedin a LHTD designed for connection to a telephone line.

FIG. 31 is a block diagram of a lightweight, low power transactiondevice integrated with wireless telephone components to make a LHTD 3100that is capable of online barcode order entry, providing bi-directionaldata-and-voice communications with an on-line server, and providingtelephone communications between live people. The display 3101,microphone 3102, barcode reader 3103, speaker 3104, keypad 3105, andcard reader 3106 are all capable of being active during order entry andtelephone communications. The barcode reader 3103 may be used off-lineto store bar codes into non-volatile memory for later use, such asstoring UPC product codes for later on-line order entry.

FIG. 32 is a block diagram of LHTD circuits. The bar code reader 3203 isan optical reader such as LED, CCD, or laser barcode reader. The cardreader 3207 may be a “smart card” or magnetic card reader. Smart cardfunctionality may also be preformed by the microprocessor 3211. Thecodec 3208 takes analog signals from an amplifier 3209 and a microphone3202 and encodes the analog signals into digital signals to be processedby microprocessor 3211. The wireless (“RF”) transceiver 3210 receivesdigital voice-and-data packets from the on-line server. Programs inmicroprocessor 3211 convert voice packets into a digital formatcompatible with codec 3208. The codec 3208 converts the digital voicesignals to analog voice signals. The analog voice signals are thenprocessed by amplifier 3209, which, in turn, drives speaker 3204 foraudio presentation to user. The microprocessor 3211 also directs some ofthe data packets received form transceiver 3210 to the display 3201 forvisual presentation to user.

The various embodiments of the LHTD, discussed above, find broadapplication in a large number of different fields. As discussed above,the LHTD provides a convenient, mobile and accessible order entry devicefor inputting product information, constructing requests based on thatproduct information, sending the requests to a server computer, andreceiving responses to the requests which the LHTD may display in avariety of different display media, including a visual text and graphicdisplay, audio tones, or printed symbols. The requests may be forordering one or more of the products specified by the input information,including, for example, products specified by barcodes. Additionalkeypad input may specify the number of products to be ordered andperhaps additional information concerning the order, includingdestination for receiving the products, the account to bill, and othersuch information, etc. These various aspects of the order may beincluded in a single request or may be included in a number ofsuccessive requests sent to the computer server.

An especially convenient feature of the LHTD is that a user mayindicate, through keypad input, a desire to speak directly with a humanoperator rather than exchanging requests with a computer server. Becausethe LHTD supports normal voice communications, just as a standardtelephone, the transition from digital requests targeted for a servercomputer to analog or digitized voice communications with a humanoperator is straightforward. Moreover, because in certain embodimentsthe LHTD can be operated while uncoupled from the telecommunicationslink using stored electrical energy, as described above, the LHTD can beused to input request data and store that input request data fortransmission to a server computer at a later time.

The LHTD may be used to solicit additional information about a productindicated by a barcode or keypad input. Thus, a printed advertisementthat included barcode indicators can easily be turned into a talkingadvertisement by use of the LHTD, providing additional information inthe form of spoken dialog or even music. The LHTD can be employed toprovide updated information on arrival and departure times and seatassignments for a flight corresponding to a printed airline ticket. Thespoken dialog can, in addition, be presented in any number of differentforeign languages, with the keypad of the LHTD used to select thedesired spoken language. A children's book that included barcodes orother LHTD-readable indications along with the text and pictures canbecome, with the use of the LHTD, a talking or multimedia children'sbook including spoken dialog, music, and perhaps additional informationdisplayed through the visual display of the LHTD. The LHTD can be usedfor all manners of inventory operations, including monitoring supplies,ordering supplies, and inquiring about alternative providers forsupplies. The LHTD can provide the power of a server computer, includingcomplex database applications and multimedia presentations via atelecommunications link to the small, hand-held, inexpensive LHTD. TheLHTD is thus essentially a multimedia terminal that can be remotelyconnected to a server computer. A LHTD might be used in a householdkitchen for purchasing groceries, storing and displaying recipes, fordiagnosing problems and failures in kitchen appliances, and for quicklyobtaining poison control information for household products in kitchencabinets.

Because the LHTD contains a microprocessor, the LHTD can communicatewith a server computer in a variety of different, relatively high-levelcommunication protocols, including TCP/IP. Thus, the LHTD is an Internetcompatible device. Alternatively, the LHTD can be directly connected viaa modem bank to a computer, without necessarily employing TCP/IP, andwithout using the Internet. In yet additional embodiments of the LHTD,the input/output, and microprocessor components of the LHTD may belocated in a different physical unit from the transceiver component ofthe LHTD, with the two components coupled by radio frequency or opticalcommunications. In this embodiment, the input/output components of theLHTD are even more mobile and easy to use. Two LHTDs may communicatewith each other via a shared telecommunications link.

Although the present invention has been described in terms of oneembodiment, it is not intended to be limited to this embodiment.Modifications within the sphere of the invention would be apparent tothose skilled in the art. For example, a large number of differentpower-management strategies can be employed to insure that the hand-helddevice can operate efficiently and for relatively long periods of timeusing the electrical power available from the telecommunications link.As discussed above, capacitors and batteries can be used to storeelectrical power obtained from the telecommunications link for lateruse. As another example, many different types of input and outputdevices may be employed. The LHTD may include various types of barcodereaders, including single point band readers, CMOS image sensor readers,CCD readers, and low-power laser readers, and may also include varioustypes of magnetic credit card readers, various types of electronic smartcard readers, any number of different types of visual displays, keypads,sound generators, and sound input devices. The LHTD may include anynumber of different combinations of these input and output devices. Awide variety of different types and models of processors, voltageregulators, transceivers, amplifiers, microprocessors, and input andoutput devices can be used to build the LHTD. For example, thetransceiver component may be implemented using any number of differentmodem chips, including V22, V29, V31, V32, and V34 chips. The V34 andV32 chips are Internet compatible, while the V29 and V31 chips are notInternet compatible, but provide very fast connect times. A wirelessLHTD device may use both an RF transceiver to establish connection tothe PSTN and a modem to communicate with a dial-up modem service orInternet Access Provider. Alternatively, the RF transceiver may be usedin a wireless LHTD to communicate data-and-voice packets with the celland have the cell provide the necessary data conversions and connectionsfor Internet access. The LHTD may be used in literally thousands ofdifferent applications, having a breath of applicability larger, in manyrespects, than personal computers or laptop computers. For example, theLHTD contains hardware support for secure transactions using credit cardnumbers whereas personal computers generally do not support fully securetransactions because they lack fully protected memory. In fact, the LHTDmay be employed as an add on to a personal computer for acquiringmagnetic credit card numbers and electronic smart card numbers inencrypted forms for use in commercial transactions, avoiding input ofthis type of sensitive information in unencrypted form into the memoryof the personal computer.

The foregoing description, for purposes of explanation, used specificnomenclature to provide a thorough understanding of the invention.However, it will be apparent to one skilled in the art that the specificdetails are not required in order to practice the invention. Theforegoing descriptions of specific embodiments of the present inventionare presented for purpose of illustration and description. They are notintended to be exhaustive or to limit the invention to the precise formsdisclosed. Obviously, many modifications and variations are possible inview of the above teachings. The embodiments are shown and described inorder to best explain the principles of the invention and its practicalapplications, to thereby enable others skilled in the art to bestutilize the invention and various embodiments with various modificationsas are suited to the particular use contemplated. It is intended thatthe scope of the invention be defined by the following claims and theirequivalents:

What is claimed is:
 1. A hand-held device for inputting request data,constructing a request, transmitting the request to a server computerthrough a telecommunications link, receiving a response to the requestfrom the server computer, and outputting the response, the hand-helddevice coupled to a telecommunications link through which the request istransmitted and the response is received, the hand-held devicecomprising: a number of input components for inputting request data froma number of different input media, including audio tones and mechanicalmanipulation of an input component and at least one of additional inputmedia including electronic, magnetic, and printed request data; aprocessing component that constructs a request from the request data; atransceiver component that sends the request to the server computer andreceives the response from the server computer; and a number of outputcomponents that output a portion of the response received from theserver computer in a particular response output medium.
 2. The hand-helddevice of claim 1 including a microphone input component that inputsaudio data, including voice data.
 3. The hand-held device of claim 1including a scanner input component that inputs printed images andcharacters.
 4. The method of claim 1 wherein the hand-held deviceincludes a keypad input component for inputting an input requestrepresented by mechanical manipulation of the keypad.
 5. The hand-helddevice of claim 1 including a magnetic card reader input component thatinputs magnetically encoded data.
 6. The hand-held device of claim 1including an electronic smart card reader input component that inputselectronically encoded data.
 7. The hand-held device of claim 1including a printed bar code reader input component that inputs datarepresented by printed bar codes.
 8. The hand-held device of claim 1including an output component that outputs alphanumeric symbols.
 9. Thehand-held device of claim 1 including an output component that outputsalphanumeric symbols.
 10. The hand-held device of claim 1 including anoutput component that outputs alphanumeric symbols and graphical images.11. The hand-held device of claim 1 including an audio speaker outputcomponent.
 12. The hand-held device of claim 1 including a printeroutput component.
 13. The hand-held device of claim 1 wherein theprocessing component is a microprocessor and wherein the microprocessorruns a number of software routines that construct requests from inputrequest data and that manage the activation and deactivation ofcomponents within the hand-held device in order to conserve electricalpower consumption by the hand-held device.
 14. The hand-held device ofclaim 13 wherein, under control of the software routines executed by themicroprocessor, an input component is activated when input data isavailable for that input component and the input component isdeactivated once data input is completed.
 15. The hand-held device ofclaim 13 wherein, under control of the software routines executed by themicroprocessor, a transmission component of the transceiver is activatedto send the request, upon completion of sending the request, thetransmission component is deactivated and a reception component of thetransceiver is activated, and upon completion of receiving the response,the reception component is deactivated.
 16. The hand-held device ofclaim 13 wherein, under control of the software routines executed by themicroprocessor, an output component is activated when output for thatoutput component is included in the response and is deactivatedfollowing completion of output of the response.
 17. The hand-held deviceof claim 13 wherein the hand-held device includes a bar code reader andwherein a proximity detector within the bar code reader is used toensure that a reflective surface that might contain a bar code issufficiently close to the bar code reader before activating the bar codereader for reading a bar code.
 18. The hand-held device of claim 17wherein the microprocessor in the hand-held device is powered down whilethe proximity detector of the bar code reader is detecting the proximityof a reflective surface and wherein, and, once a bar code has been read,a bar code microprocessor within the bar code reader signals themicroprocessor in the hand-held device to power up the microprocessor inthe hand-held device in order to process the bar code.
 19. The hand-helddevice of claim 17 wherein the bar code reader includes a bank ofillumination elements that together illuminate a bar code to be read,and wherein the proximity detector comprises a subset of theillumination elements that provide sufficient illumination to detect areflective surface.
 20. The hand-held device of claim 17 wherein inputcomponents that receive amplified signals receive amplified signals fromdual power mode amplifiers such that, when no signals are being input tothe input components, the dual power mode amplifiers are in a low-powerstate in order to conserve consumption of electrical power by thehand-held device.
 21. The hand-held device of claim 1 further includinga protected memory that stores input information that must be protectedfrom access by external devices and that is transmitted in an encryptedform from the hand-held device to the telecommunications link.
 22. Thehand-held device of claim 1 further including a tone generator outputcomponent that sends multiple frequency tones that do not occur invoice-generated analog signals that serve as out-of-band signals to areceiving transceiver connected to the remote server computer.
 23. Thehand-held device of claim 22 wherein a multiple frequency tone is sentby the tone generator to interrupt analog communications being receivedfrom the remote server computer.
 24. The hand-held device of claim 23wherein multiple frequency tones are sent by the tone generator toinitialize data exchange between the hand-held device and the remoteserver computer, including to set the baud rate, protocol, and othercommunications parameters prior to sending a request.
 25. The hand-helddevice of claim 1 wherein the telecommunications link is a telephoneline.
 26. The hand-held device of claim 1 wherein the telecommunicationslink is an RS232 connection to a computer that is linked to the servercomputer.
 27. The hand-held device of claim 26 wherein the hand-helddevice is also coupled to a telephone line and uses internal levelshifting method, such as optical coupling, to enable drawing currentfrom both the RS232 connection and the telephone line.
 28. The hand-helddevice of claim 1 wherein the telecommunications link is a universalserial bus connection to a computer that is linked to the servercomputer.
 29. The hand-held device of claim 28 wherein the hand-helddevice is also coupled to a telephone line and uses internal levelshifting method, such as optical coupling, to enable drawing currentfrom both the RS232 connection and the telephone line.
 30. The hand-helddevice of claim 1 wherein the telecommunications link is a wirelesstelephone.
 31. The hand-held device of claim 1 wherein thetelecommunications link is a cellular telephone.
 32. The hand-helddevice of claim 1 wherein the telecommunications link is a personalcommunications system telephone.
 33. The hand-held device of claim 1wherein the telecommunications link is a PBX telephone line.
 34. Thehand-held device of claim 1 wherein the transceiver component isincluded in a first unit and the input, output, and processingcomponents are included in a second unit, wherein the first unit andsecond unit are coupled by communications via optical signals or radiofrequency signals.
 35. The hand-held device of claim 1 wherein the inputcomponent comprises a laser bar code reader.
 36. The hand-held device ofclaim 1 wherein the input component comprises a LED bar code reader. 37.The hand-held device of claim 1 wherein the input component comprises aCCD bar code reader.
 38. The hand-held device of claim 1 furtherincluding one or more energy storing devices selected from capacitorsand batteries that obtain electrical power from the telecommunicationslink when the hand-held device is connected to the telecommunicationslink and that provide electrical power to the hand-held device when thehand-held device is not connected to the telecommunications link. 39.The hand-held device of claim 1 includes a telephone forperson-to-person or person-to-computer server voice communications viatelecommunication link.
 40. The hand-held device of claim 1 wherein theinput component comprises or output component comprises a serialinterface such as RS232.